Fire swamps are more than just folk legend

Plus other fun facts from The Weirdest Thing I Learned This Week.
a still from the film, The Princess Bride
Fire swamps could be real, though they'd look a bit different than ROUS territory. The Princess Bride

What’s the weirdest thing you learned this week? Well, whatever it is, we promise you’ll have an even weirder answer if you listen to PopSci’s hit podcastThe Weirdest Thing I Learned This Week hits AppleSpotifyYouTube, and everywhere else you listen to podcasts every-other Wednesday morning. It’s your new favorite source for the strangest science-adjacent facts, figures, and Wikipedia spirals the editors of Popular Science can muster. If you like the stories in this post, we guarantee you’ll love the show.

FACT: Roaches are changing the way they have sex, and it’s all our fault (again)

By Rachel Feltman

A recent study showed that human interference may have had a big impact on the way German cockroaches romance one another—and this isn’t even the first time that’s happened. 

When it’s time to do the deed, a male cockroach will provide a “nuptial gift” to his female of choice. It’s a solution full of proteins, fats and sugars, so it’s sort of like giving chocolate to someone you’re trying to woo (if you secreted that chocolate from a gland under your wings). The goo contains maltose, which quickly turns into glucose when it hits a female’s saliva. 

The delicious gift entices the female to climb up onto her sugar daddy’s back for easier access, which gives him an opportunity to latch his hooked, telescoping penis (!) onto her reproductive tract. Then they face in opposite directions, attached at the bum, and stay that way for an hour and a half. And they say romance is dead! 

Humans screwed this process up in the late 20th century. Because roaches love sweet treats—nuptial and otherwise—researchers created pesticides containing glucose to tempt them into poisoning themselves. It worked so well that by the 1980s, there were German roach populations in Florida who no longer sought out sweet stuff to eat. Several other populations have shown similar mutations since then. Basically, hijacking the cockroach sweet tooth was so effective that bugs with weird sugar-hating mutations were doing all the baby-making. 

That’s a real problem for amorous male roaches. Last year, researchers confirmed that females with the glucose aversion mutation actively avoided male nuptial gifts. They’d run off from the mating attempt as soon as they got a taste of something other than fat and protein.

Unfortunately for us, it seems like roaches have created a solution all by themselves. In a study published in April, scientists showed that glucose-averse male cockroaches have developed two traits to deal with this issue. For one, they’ve started to secrete less maltose and more maltotriose. It’s a more complex sugar molecule that takes five minutes to break down into glucose in the female’s saliva. Females seem to like it better even when they don’t have the glucose-aversion mutation, and the long delay keeps glucose-averse maidens from scurrying off in disgust. The males have also gotten faster in doing their chocolate-to-penis bait and switch. It usually takes a male three to four seconds to lock their genitalia onto a female’s, but scientists say the ones they observed had shaved around a second off of that time. Meanwhile, the females seem to be developing changes in their saliva that make the process of turning maltose or maltotriose into glucose even slower. 

For more weird animal sex, check out my book!

FACT: Fire swamps à la Dark Souls and The Princess Bride have a real-life counterpart

By Jess Boddy

I was inspired to research this fact during a recent playthrough of Dark Souls I was doing on Twitch. As I traversed the infamous Blighttown swamp, zweihander in hand, it struck me how wild it is that there’s an entirely separate zone situated just beneath all of the poison gunk—a fire zone. And sometimes, as with the spider boss Quelaag, that fire seeps up through the poison gunk. And that made me think of The Princess Bride, a wonderful film that has a swamp where fire spurts from the ground. So I was thinking, why are fire swamps a thing? Could they exist in real life?

Reader, they can. There have been instances of people traversing swamps, either on foot or by boat, and they see a plume of flames. This is where a lot of swamp ghost stories come from. For example, in some European folklore, these fireballs were thought to be satanic sprites that could wield fire, and these were called will-o-the-wisps! 

So, yes, it happens in real life… but let’s say it’s NOT ghosts. Could it be a scientific phenomenon? Well, PopSci actually did a story on this back in 2018, and a microbiologist explains how bog water is stagnant and oxygen-deprived, creating the perfect environment for anaerobic bacteria, or microorganisms that live without oxygen. Sometimes, those microbes can create the right conditions for some flammable gasses to build up.

The notion of fire swamps even go back to 1783, in what many consider to be the very first American science experiment. George Washington, waiting in Princeton, New Jersey for the freshly-signed Treaty of Paris to arrive, fiercely debated with his soldiers on whether will-o-the-wisps were ghosts or science. (A classic debate.) They paddled down the river with a torch and a long stick, literally probing for an answer. Then, apparently, moments later, a “great, big flash” erupted from the water. So… fire swamp!

Listen to this week’s episode to hear more about real-life fire swamps and how Dark Souls’ connection of chaos and pyromancy also has roots in science.

FACT: Scientific scammers are everywhere. Here’s how to spot them

By Amanda Reed

Scientific scams are more common than we think. The “vaccines cause autism” study: scientific scam! The deeply flawed original 1998 study by Andrew Wakefield was retracted and he had his medical license revoked for it, but people still run with it today. Elizabeth Holmes and Theranos: scientific scam! Thernanos’ Edison testing device was not doing anything magical with fingerpricks of blood, and now she’s is serving time for it. What defines a scientific scam, or scientific misconduct? Per the National Academy of Sciences’ “On Being a Scientist: A Guide to Responsible Conduct in Research, scientific misconduct is “fabrication, falsification, or plagiarism in proposing, performing, or reviewing research, or in reporting research results.” It ranges from using Photoshop to manipulate images and graphs to even abuse of confidentiality in peer review. But there are ways to spot them—you just have to listen to the episode to learn more.